Neoadjuvant chemotherapy in locally advanced colon cancer: a systematic review and meta-analysis

Impact of gut microbiota on colorectal anastomotic healing (Review)

Intestinal anastomosis is a critical procedure in both emergency and elective surgeries to maintain intestinal continuity. However, the incidence of anastomotic leakage (AL) has recently increased, reaching up to 20%, imposing major clinical and economic burdens. Substantial perioperative alterations in the intestinal microbiota composition may contribute to AL, particularly due to disruptions in key microbial populations essential for intestinal health and healing. The intricate interplay between the intestinal microbiota and the host immune system, along with microbial changes before and during surgery, significantly influences anastomotic integrity. Notably, specific pathogens such as Enterococcus and Pseudomonas aeruginosa have been implicated in AL pathogenesis. Preventive strategies including dietary regulation, personalized intestinal preparation, microbiota restoration and enhanced recovery after surgery protocols, may mitigate AL risks. Future research should focus on elucidating the precise mechanisms linking intestinal microbiota alterations to anastomotic healing and developing targeted interventions to improve surgical outcomes.

Neoadjuvant chemotherapy improves overall survival in stage III but not in stage II colon cancer: A propensity score-matched analysis of the National Cancer Database

BACKGROUND

Neoadjuvant chemotherapy has been recently suggested for advanced colon cancer, but little is known about the impact on short-term outcomes and overall survival. In this study, we aimed to evaluate the effect of neoadjuvant chemotherapy on survival in stage II-III colonic adenocarcinoma.

METHODS

A retrospective analysis of the colon cancer US National Cancer Database from 2006 to 2019 was performed. Patients treated with neoadjuvant chemotherapy were matched using propensity score to controls (ratio 1:1). The primary outcome was 5-year overall survival.

RESULTS

In total, 1,275 patients (1.3%) with clinical stage II-III colonic adenocarcinoma received neoadjuvant chemotherapy. After matching, the neoadjuvant chemotherapy group included 783 patients. The restricted mean 5-year overall survival in the neoadjuvant chemotherapy group was significantly higher compared with controls (48.9 vs 44.9 months, P = .003). Stratified by disease stage, neoadjuvant chemotherapy was associated with a significantly longer overall survival (47.5 vs 41.2 months; P = .001) in stage III while showing an equivalent overall survival in stage II (50.3 vs 48.6 months; P = .2). The benefit in overall survival was pronounced in stage T4 and positive nodal disease. Cox regression analysis in patients with stage III revealed that neoadjuvant chemotherapy was associated with a 21% reduction in mortality risk (hazard ratio, 0.79; 95% confidence interval, 0.65-0.96; P = .01). Neoadjuvant chemotherapy was associated with lower rates of 30-day readmission (3.5% vs 7.4%, P = .001), 30-day mortality (0.9% vs 3.8%, P < .001), and 90-day mortality (2.9% vs 8.5%, P < .001).

CONCLUSION

Preoperative neoadjuvant chemotherapy is associated with improved overall survival in patients with stage III colon cancer, mainly in patients with T4 disease.

Adenocarcinoma of the duodenal papilla with synchronous peritoneal metastases-5 years of overall survival: A case report

BACKGROUND

Ampullary adenocarcinomas are a rare disease. They can be classified anatomically or according to their histology into intestinal, pancreatobiliary, and mixed subtypes, with different subtypes having distinct prognoses and potential treatments. We report a clinical case of a patient with mixed type adenocarcinoma of the ampulla of Vater, with predominantly intestinal histology, associated with an isolated and synchronous peritoneal carcinomatosis. It is the only case reported in the literature of duodenal ampulla cancer with synchronous peritoneal metastases, with long-term survival.

CASE SUMMARY

A 53-year-old male patient with non-insulin-dependent diabetes presented with acute abdominal pain in the right hypochondrium. Images revealed dilatation of the biliary tract and the duct of Wirsung, without a clear obstructive factor. Upper gastrointestinal endoscopy revealed a tumor in the duodenal papilla. Biopsies confirmed an adenocarcinoma. In the first surgical step, a biliodigestive bypass was performed in association with resection of the carcinomatosis. Peritoneal metastases was found during the intraoperative period. Subsequently, chemotherapy with the folinic acid, fluorouracil, and oxaliplatin regimen was administered based on histology, and a favorable response was achieved. After a multidisciplinary discussion, the Whipple procedure was performed. A delayed biopsy showed disease-free margins. The patient achieved 5 years of overall survival in August 2024, and 4 years of disease-free survival in September 2024.

CONCLUSION

We conclude that an important value of this work is showing individualized treatment for a patient with cancer.

The Role of Prehabilitation in Oncology Patients Undergoing Complex Systemic Anticancer Therapy

OBJECTIVES

To review the recent literature around the role of patient-centric prehabilitation for oncology patients undergoing complex systemic anticancer therapy (SACT) and the nurse's role in this area.

METHOD

A narrative review of recent peer-reviewed literature, national guidance, and government strategy for prehabilitation in oncology patients undergoing complex SACT.

RESULTS/CONCLUSION

Prehabilitation interventions in people receiving complex SACT are feasible and benefit patient outcomes. These results must still be viewed with caution; however, as of now, there are only small-scale studies in this area, although larger-scale studies are now being done. The role of the nurse is key here (as part of the interdisciplinary team) through the establishment of the therapeutic relationship underpinning patient screening, assessment, intervention implementation, and patient reassessment, ensuring care is dynamic, consistent, and tailored to patient needs.

IMPLICATIONS FOR NURSING PRACTICE

The review has discussed the beneficial patient outcomes from prehabilitation in patients receiving complex SACT, but more research is warranted in the form of larger multisite trials to increase the validity of the prehabilitation interventions. The review advocates for the role of the nurse in the provision of prehabilitation in SACT oncology patients through the provision of personalized patient care.

Development and validation of cancer-specific survival prediction nomogram for patients with T4 stage colon cancer after surgical resection: a population-based study

PURPOSE

The increasing incidence of colorectal cancer has coincided with a rise in T4 stage colon cancer (CC), yet research on its prognosis remains limited. This study aimed to identify risk factors and develop a nomogram to predict cancer-specific survival (CSS), optimizing treatment strategies for different subgroups.

METHODS

Using data from the from the Surveillance, Epidemiology, and End Results (SEER) database, we identified risk factors in T4 stage CC patients and created a nomogram to predict CSS. Patients were divided into low- and high-risk groups, and the nomogram was validated. Propensity score matching was used to evaluate the benefits of various therapies across subgroups.

RESULTS

Independent risk factors, including T stage, N stage, tumor grade, age, and therapy sequence, were identified through Cox regression analyses and incorporated into the nomogram. The nomogram outperformed the American Joint Committee on Cancer (AJCC) 7th staging system, with a Concordance-index of 0.77 in both training and validation sets. The receiver operating characteristic curves showed area under the curve values of 0.81, 0.77, and 0.75 for 1-, 3-, and 5-year CSS, respectively. Calibration plots confirmed strong alignment between predicted and actual outcomes, and decision curve analysis highlighted the nomogram's superior clinical utility. Chemotherapy significantly improved CSS, while radiation did not. Adjuvant therapy was particularly beneficial in high-risk groups.

CONCLUSION

This study offered a thorough prognostic analysis of T4 stage colon cancer patients and developed nomograms for predicting CSS. Subgroup analyses highlight the potential benefits of various treatment options.

Neoadjuvant chemotherapy in locally advanced colon cancer: A systematic review with proportional meta-analysis

Neoadjuvant chemotherapy is suggested in locally advanced colon cancer. Data on improved long-term oncological outcomes are lacking, which hampers the implementation in clinical practice. This systematic review provides an overview of the benefits and drawbacks of neoadjuvant chemotherapy in patients with locally advanced colon cancer. A systematic literature search was performed using Embase (OVID), MEDLINE (OvidSP), and the Cochrane Library. Studies reporting on the efficacy of neoadjuvant chemotherapy in patients with operable, locally advanced colon cancer without metastases at the time of diagnosis were considered eligible for inclusion. An overview of short- and long-term outcomes of neoadjuvant chemotherapy is provided based on available literature. Additionally, proportional meta-analyses were performed using MedCalc Statistical Software version 19.2.6. A total of 17 unique studies were included in this review, 3 randomised controlled trials and 14 prospective single-arm or retrospective studies. The maximum reported dropout before surgery was 7.8 % in the neoadjuvant chemotherapy group. A histopathological complete response after neoadjuvant chemotherapy was observed in 0-4.8 % of the patients. The occurrence of anastomotic leaks was less than 8 % for both patients treated with neoadjuvant chemotherapy and patients treated with upfront surgery. Neoadjuvant chemotherapy is a safe alternative for adjuvant chemotherapy based on the dropout rate before surgery and the peri-operative morbidity and peri-operative mortality. Robust long-term survival outcomes are lacking and serious concerns regarding the risk of overtreatment have been expressed. Hence, neoadjuvant chemotherapy might be considered in a select group of patients with locally advanced colon cancer.

High-performance CT features supporting accurate pre-operative tumor staging in colon cancer

Background and aims

Accurate pre-treatment tumor staging is essential for treatment decision-making. Multi-slice spiral computed tomography (CT) is currently the standard method for pre-operative clinical tumor staging, but accurately applying the CT findings in tumor staging remains a challenge due to the poor pathological understanding of the CT signs. We aimed to pathologically interpret the key CT findings in order to identify reliable markers for pre-treatment staging of colon cancer.

Patients and methods

The following CT features from 136 colon adenocarcinomas were analyzed: colon wall pliability, outline contour, pericolic fat attenuations and vascularity, tumor fusion with adjacent organs, ascites, tumor size, and relevance between tumor and retroperitoneal fascia. These CT features were corroborated with histopathological findings. The diagnostic performance of these was further analyzed.

Results

Based on the postoperative pathological tumor staging (pT), 136 colon adenocarcinomas were classified into four stages: pT1 (n = 5), pT2 (n = 7), pT3 (n = 96), and pT4 (n = 28). Key findings include the following: (1) soft colon wall is a characteristic of the pT1 tumors, whereas stiff colon wall is a characteristic of the pT2~pT4 tumors; pathologically, stiff colon wall reflects the infiltration of tumor cells with desmoplastic reaction (DR) in muscularis propria; (2) small protuberances may help exclude the pT2 tumors. Histopathologically, small protuberances in pT2 cancer represent the pure DR on the surface of lamina propria, whereas the small protuberances in pT3~pT4 cancers represent the sub-serosal or extra-serosal cancer cell foci enwrapped by DR; (3) the presence of large protuberances, extensive reticulonodular fat stranding, and fusion with surrounding organs and ascites are diagnostic of pT4 tumors; and (4) the presence of extra-fascial nodules/streaks on CT scan could accurately diagnose the ascending/descending colon cancer of pT4 stage. Histologically, the presence of the above five CT features (large protuberances, extensive reticulonodular fat stranding, fusion with surrounding organs, ascites, and extra-fascial nodules/streaks) reflect the farther and deeper infiltration of tumor cells in serosa or retroperitoneal fascia involvement.

Conclusion

Our studies have identified multiple CT features that are practically useful in identifying and differentiating different stages of colon cancer prior to surgical procedures. These high-performance markers will provide valuable insights to the clinicians in making appropriate decisions in the management of patients with colon cancer.

Oncologic oUTcomes of neoadjuvant chemotherapy for obSTructive colon cAncer after steNt decompression (OUTSTAND trial); A study protocol of multicenter non-inferiority randomized controlled trial

BACKGROUND

For obstructive colon cancer, many studies have been conducted on the use of self-expandable metallic stents (SEMS) as a bridge to surgery (BTS). However, there are currently no available prospective data on the impact of bridging period and there is a lack of research on the effects of neoadjuvant chemotherapy during the bridging period.

OBJECTIVES

Patients who undergo successful SEMS placement for obstructive left-sided colon adenocarcinoma without metastases will be eligible for this study.

DESIGN

This study is a multicenter, non-inferiority, randomized (1:1), open-label, controlled trial.

METHODS & ANALYSIS

The patients assigned to the control group will undergo curative surgery within two weeks after successful SEMS placement. The patients assigned to the experimental group will undergo three cycles of neoadjuvant FOLFOX chemotherapy within two weeks after successful SEMS placement. Curative surgery will be performed within four weeks of the last administration of neoadjuvant FOLFOX. Circulating tumor DNA (ctDNA) will be collected at specific time points.

DISCUSSION

The optimal time interval for SEMS placement as a BTS can significantly impact long-term oncologic outcomes. In this study, our goal is to identify the optimal time interval for SEMS placement as a BTS. Recently, there has been interest in applying neoadjuvant chemotherapy for locally advanced colon cancer. In the context of early treatment for tumor dissemination following SEMS placement, neoadjuvant chemotherapy may be beneficial for delayed surgery after SEMS placement as a BTS. The results of this trial will be an important reference for the application of neoadjuvant chemotherapy in locally advanced colon cancer. Additionally, researchers will investigate whether ctDNA can serve as a reliable indicator to guide decisions about the timing and type of subsequent treatment. Based on the results of this trial, a patient-tailored treatment strategy can be developed for obstructive colon cancer.

REGISTRATION

This study is registered on ClinicalTrials.gov Identifier: NCT04889820, registered on May 17, 2021 in clinicaltrials.gov; Protocol ID: XC21MIDI0004.

Self-Expandable Metal Stents for Obstructing Colon Cancer and Extracolonic Cancer: A Review of Latest Evidence

Colorectal cancer (CRC) is a leading cause of cancer mortality, with many patients presenting with malignant colorectal obstruction (MCO). Self-expandable metal stents (SEMSs) have emerged as a minimally invasive key intervention, both as a bridge to surgery (BTS) in curative setting sand for palliation in advanced disease. This review aims to provide an evidence-based analysis of SEMS indications, contraindications, and efficacy across curative and palliative contexts, with focus on long-term outcomes. Based on data from recent trials and guidelines, we examine SEMS placement outcomes, focusing on specific scenarios, including BTS for left-sided MCO, chemotherapy (with angiogenic agents) safety during stent therapy, the optimal timing between SEMS placement and surgery, and oncological outcomes. We also discuss the use of SEMSs in challenging contexts such as proximal colon obstruction and extracolonic obstruction, and the relevant technical considerations. Findings indicate that using a SEMS in the BTS setting reduces emergency surgery needs, minimizes complications, and decreases stoma formation. Long-term oncologic outcomes, particularly recurrence, are still debated, but recent evidence shows that SEMS placement is safe, without worsening long term outcomes. Palliative SEMS placement shows high efficacy in symptom relief with manageable adverse events. Success depends on patient selection and technical expertise, with multidisciplinary approaches essential for optimal outcomes.

The Clinical Characteristics of a Stage II Colorectal Cancer T4 Tumor: A Ten-Year Single-Center Research Report

AIM

The tumor staging of colorectal cancer (CRC) plays a significant role in both treatment and prognosis, impacting surgical planning and adjuvant therapy decisions. Currently, the staging of CRC is based on the TNM system developed by the American Joint Committee on Cancer. Prior studies have suggested that survival rates and recurrent rates of T4a tumors appear to be worse than that of T4b tumors, although there is currently no consensus. Therefore, we collected patient data from Taichung Veterans General Hospital over the past decade in order to conduct further research.

METHOD

Between 2010 and 2018, a total of 5760 newly diagnosed CRC patients were seen at the hospital. To eliminate the influence of any local lymph node involvement or distant organ metastasis on the research results, we focused on patients with pathologic Stage IIc disease (T4a-bN0M0). Patients with rectal cancer who had received neoadjuvant concurrent chemoradiotherapy were excluded. Ultimately, 132 patients were included in this study. A multivariate Cox regression analysis was conducted to identify independent risk factors for both 10-year cancer-specific survival (CSS) and overall survival (OS).

RESULTS

A total of 132 patients were included in the study, with 90 classified as T4a and 42 as T4b. The 10-year CSS for pT4a and pT4b was 72.5% and 56.5%, respectively, with a p-value of 0.011. The 10-year OS for pT4a and pT4b was 48.4% and 42.5%, respectively, with a p-value of 0.086. There was no significant difference in the site of first recurrence between the pT4a and pT4b groups (p-value = 0.936). Overall, patients who received adjuvant chemotherapy therapy had a significantly better prognosis (p-value < 0.05). However, there was no significant difference in prognosis between oral 5-FU and FOLFOX.

CONCLUSION

Based on our data, patients diagnosed with pathologic T4aN0M0 CRC appeared to experience a trend toward better 10-year OS when compared to those with T4bN0M0 disease, but this trend lacks statistical significance. Patients with locally advanced Stage II colon cancer clearly benefited from adjuvant chemotherapy therapy; therefore, FOLFOX may not necessarily be required.

Perioperative outcomes of sinusoidal obstruction syndrome in patients undergoing liver resection for colorectal metastases after neoadjuvant chemotherapy: a retrospective cohort research

Purpose

We investigated the factors that affect the occurrence of sinusoidal obstruction syndrome (SOS) and the effect of SOS on the patient's perioperative outcomes through histological review of liver resection specimens from patients who underwent chemotherapy.

Methods

From December 2007 to December 2020, liver specimens from patients who underwent liver resection for colorectal liver metastasis after neoadjuvant chemotherapy were analyzed regarding liver damage in the nontumorous lesion. Through pathological review, patients with grade 1-3 sinusoidal dilatation were categorized into the SOS (+) group, compared to a control group (grade 0, SOS [-]).

Results

Of 286 patients, 175 were included. Preoperative factors were similar between the groups. Although not statistically significant, the SOS (+) group had a shorter chemotherapy-free interval before resection (7.96 weeks vs. 10.0 weeks, P = 0.069). The SOS (+) group had higher intraoperative blood loss (889.1 ± 1,126.6 mL vs. 555.3 ± 566.7 mL, P = 0.012) and transfusion rates (46.6% vs. 25.3%, P = 0.003). SOS correlated with increased liver surgery-specific complications (40.9% vs. 26.4, P = 0.043). Patients with SOS experienced adverse effects on intrahepatic recurrent-free survival and overall survival (5-year survival, 46.0% vs. 33.9%; P = 0.014).

Conclusion

SOS development during liver surgery is associated with increased intraoperative blood loss, transfusion volume, and liver surgery-specific complications and has a higher risk of early recurrence and decreased overall survival. Thus, it is crucial to exercise caution during liver surgery in these patients.

Neoadjuvant Chemotherapy in Colon Cancer: More Than Just an Optical Illusion

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Neoadjuvant Chemotherapy With Oxaliplatin and Fluoropyrimidine Versus Upfront Surgery for Locally Advanced Colon Cancer: The Randomized, Phase III OPTICAL Trial

PURPOSE

The role of neoadjuvant chemotherapy (NAC) in colon cancer remains unclear. This trial investigated whether 3 months of modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) or capecitabine and oxaliplatin (CAPOX) as NAC could improve outcomes in patients with locally advanced colon cancer versus upfront surgery.

PATIENTS AND METHODS

OPTICAL was a randomized, phase III trial in patients with clinically staged locally advanced colon cancer (T3 with extramural spread into the mesocolic fat ≥5 mm or T4). Patients were randomly assigned 1:1 to receive six preoperative cycles of mFOLFOX6 or four cycles of CAPOX, followed by surgery and adjuvant chemotherapy (NAC group), or immediate surgery and the physician's choice of adjuvant chemotherapy (upfront surgery group). The primary end point was 3-year disease-free survival (DFS) assessed in the modified intention-to-treat (mITT) population.

RESULTS

Between January 2016 and April 2021, of the 752 patients enrolled, 744 patients were included in the mITT analysis (371 in the NAC group; 373 in the upfront surgery group). At a median follow-up of 48.0 months (IQR, 46.0-50.1), 3-year DFS rates were 82.1% in the NAC group and 77.5% in the upfront surgery group (stratified hazard ratio [HR], 0.74 [95% CI, 0.54 to 1.03]). The R0 resection was achieved in 98% of patients who underwent surgery in both groups. Compared with upfront surgery, NAC resulted in a 7% pathologic complete response rate (pCR), significantly lower rates of advanced tumor staging (pT3-4: 77% v 94%), lymph node metastasis (pN1-2: 31% v 46%), and potentially improved overall survival (stratified HR, 0.44 [95% CI, 0.25 to 0.77]).

CONCLUSION

NAC with mFOLFOX6 or CAPOX did not show a significant DFS benefit. However, this neoadjuvant approach was safe, resulted in substantial pathologic downstaging, and appears to be a viable therapeutic option for locally advanced colon cancer.

Comparison of partial and total cystectomy for colorectal cancer with histologically confirmed bladder invasion

BACKGROUND

Although organs are preserved and quality of life is improved, insufficient evidence is available for the oncologic safety of partial cystectomy in patients with colorectal cancer with suspected bladder invasion. Therefore, we aimed to compare partial and total cystectomy outcomes in patients with pathologically confirmed or clinically suspected bladder invasion.

METHODS

Patients with colorectal cancer with suspected bladder invasion who underwent R0 resection from 2000 to 2020 were evaluated. Long-term outcomes were determined in patients with histologically confirmed bladder invasion.

RESULTS

Of the 151 consecutive patients, 96 (64.6%) had histologically confirmed bladder involvement, and 105 (69.5%) underwent partial cystectomy. Operative time, estimated blood loss, and reoperation rate in ≤30 days were significantly worse in the total cystectomy group than in the partial cystectomy group. The overall recurrence rate was significantly higher in the total cystectomy group than in the partial cystectomy group (39.1% vs 21.9%; P = .046). Five-year overall survival (75.8% vs 53.2%; P = .006) rates were higher in the partial cystectomy group than in the total cystectomy group; however, disease-free survival (60.8% vs 41.6%; P = .088) rates were similar in patients with suspected bladder invasion. In patients with histologically confirmed bladder invasion, 5-year overall survival rates (78.1% vs 52.1%; P = .017) were higher in the partial cystectomy group than in the total cystectomy group; however, disease-free survival rates (53.4% vs 41.2%; P = .220) did not differ significantly.

CONCLUSION

R0 resection is associated with favorable long-term outcomes in patients with locally advanced colorectal cancer. If R0 resection is possible, partial cystectomy is considered safe.

Efficacy and Safety of Neoadjuvant Subcutaneous Envafolimab in dMMR/MSI-H Locally Advanced Colon Cancer

BACKGROUND

Neoadjuvant immunotherapy with programmed death-ligand 1 blockade for colon cancer, especially for mismatch repair-deficient (dMMR)/high microsatellite instability (MSI-H) colon cancer, has gained considerable attention recently.

OBJECTIVE

This study aimed to assess the safety and efficacy of neoadjuvant subcutaneous envafolimab in patients with dMMR/MSI-H locally advanced colon cancer.

METHODS

Patients with dMMR/MSI-H locally advanced colon cancer treated with envafolimab at Sun Yat-sen University Cancer Center and Yunnan Cancer Hospital from October 2021 to July 2023 were retrospectively reviewed and analyzed. The primary endpoint was the pathological complete response (CR) rate, and secondary endpoints were treatment-related adverse events and complete clinical response rate.

RESULTS

Overall, 15 patients were analyzed. After neoadjuvant immunotherapy with envafolimab, six patients achieved a CR, with five partial responses, and four stable disease. Three patients achieving a complete clinical response chose to accept a "watch and wait" strategy, and surgery was performed in 12 patients. Postoperative pathology results revealed seven patients achieved pathological CRs, and five patients achieved tumor regression grade 2, with 66.7% of the total CR rate. The most common treatment-related adverse events were pruritus and rash (40%), with no severe cases. No recurrences occurred over a 7.9-month follow-up.

CONCLUSIONS

Envafolimab yielded promising surgical outcomes and safety in dMMR/MSI-H locally advanced colon cancer, representing a promising treatment modality for this population.

CRISPR screens reveal convergent targeting strategies against evolutionarily distinct chemoresistance in cancer

Resistance to chemotherapy has been a major hurdle that limits therapeutic benefits for many types of cancer. Here we systematically identify genetic drivers underlying chemoresistance by performing 30 genome-scale CRISPR knockout screens for seven chemotherapeutic agents in multiple cancer cells. Chemoresistance genes vary between conditions primarily due to distinct genetic background and mechanism of action of drugs, manifesting heterogeneous and multiplexed routes towards chemoresistance. By focusing on oxaliplatin and irinotecan resistance in colorectal cancer, we unravel that evolutionarily distinct chemoresistance can share consensus vulnerabilities identified by 26 second-round CRISPR screens with druggable gene library. We further pinpoint PLK4 as a therapeutic target to overcome oxaliplatin resistance in various models via genetic ablation or pharmacological inhibition, highlighting a single-agent strategy to antagonize evolutionarily distinct chemoresistance. Our study not only provides resources and insights into the molecular basis of chemoresistance, but also proposes potential biomarkers and therapeutic strategies against such resistance.

Imaging in the era of risk-adapted treatment in colon cancer

The treatment landscape for patients with colon cancer is continuously evolving. Risk-adapted treatment strategies, including neoadjuvant chemotherapy and immunotherapy, are slowly finding their way into clinical practice and guidelines. Radiologists are pivotal in guiding clinicians toward the most optimal treatment for each colon cancer patient. This review provides an overview of recent and upcoming advances in the diagnostic management of colon cancer and the radiologist's role in the multidisciplinary approach to treating colon cancer.

Gut Microbiota-Adversary or Ally? Its Role and Significance in Colorectal Cancer Pathogenesis, Progression, and Treatment

In 2022, colorectal cancer (CRC) was the third most prevalent malignancy worldwide. The therapeutic approach for CRC typically involves a multimodal regimen. The human gut microbiota comprises over 35,000 bacterial species. The composition of the gut microbiota is influenced by dietary intake, which plays a crucial role in food absorption, nutrient extraction, and the development of low-grade inflammation. Dysbiosis in the gut microbiota is a key driver of inflammation and is strongly associated with CRC development. While the gut microbiome influences CRC initiation and progression, emerging evidence suggests a role for the gut microbiome in modulating the efficacy and toxicity of cancer treatments. Therapeutic strategies targeting the gut microbiome, such as probiotics, hold promise as effective interventions in the modern therapeutical approach to CRC. For example, Microbiota Implementation to Reduce Anastomotic Colorectal Leaks (MIRACLe) implementation has resulted in improvements in clinical outcomes, including reduced incidence of anastomotic leakage (AL), surgical site infections (SSIs), reoperation, as well as shorter recovery times and hospital stays compared with the control group. Therefore, this review aims to describe the current state of knowledge regarding the involvement of the gut microbiota in CRC pathogenesis and its potential therapeutic implications to treat CRC.

Colorectal cancer: a comprehensive review of carcinogenesis, diagnosis, and novel strategies for classified treatments

Colorectal cancer is the third most common and the second deadliest cancer worldwide. To date, colorectal cancer becomes one of the most important challenges of the health system in many countries. Since the clinical symptoms of this cancer appear in the final stages of the disease and there is a significant golden time between the formation of polyps and the onset of cancer, early diagnosis can play a significant role in reducing mortality. Today, in addition to colonoscopy, minimally invasive methods such as liquid biopsy have received much attention. The treatment of this complex disease has been mostly based on traditional treatments including surgery, radiotherapy, and chemotherapy; the high mortality rate indicates a lack of success for current treatment methods. Moreover, disease recurrence is another problem of traditional treatments. Recently, new approaches such as targeted therapy, immunotherapy, and nanomedicine have opened new doors for cancer treatment, some of which have already entered the market, and many methods have shown promising results in clinical trials. The success of immunotherapy in the treatment of refractory disease, the introduction of these methods into neoadjuvant therapy, and the successful results in tumor shrinkage without surgery have made immunotherapy a tough competitor for conventional treatments. It seems that the combination of those methods with such targeted therapies will go through promising changes in the future of colorectal cancer treatment.

Effectiveness and safety of neoadjuvant apatinib in combination with capecitabine and oxaliplatin for the therapy of locally advanced colorectal cancer: A retrospective study

The goal of the present study was to appraise the efficacy and safety of neoadjuvant apatinib in combination with capecitabine and oxaliplatin (XELOX) in patients with locally advanced colorectal cancer (CRC), as relevant data on its usage in this setting are lacking. A retrospective analysis was implemented on 100 patients with locally advanced CRC who received either neoadjuvant apatinib in combination with XELOX (N=50) or neoadjuvant XELOX alone (N=50). Radiological response and pathological complete response rates were evaluated. Furthermore, the researchers obtained data pertaining to disease-free survival (DFS), overall survival, as well as adverse events. The consequences of the present study indicated that the neoadjuvant apatinib in combination with XELOX treatment approach yielded higher rates of radiological objective response (86.0 vs. 68.0%, P=0.032) and major pathological response (46.0 vs. 22.0%, P=0.011) compared with XELOX alone. These findings were further confirmed through multivariate logistic regression analyses (P=0.037 and P=0.008, respectively). Interestingly, the neoadjuvant apatinib in combination with XELOX treatment approach significantly prolonged DFS when compared with XELOX alone (P=0.033). In summary, the administration of neoadjuvant apatinib in combination with XELOX demonstrates superiority over the use of XELOX alone in terms of achieving a more favorable pathological response and a longer duration of DFS in patients diagnosed with locally advanced CRC.

Nationwide Outcomes After Neoadjuvant Chemotherapy for Locally Advanced Sigmoid Colon Cancer-A Propensity Score-Matched Analysis

BACKGROUND

The role of neoadjuvant chemotherapy (NAC) in advanced sigmoid colon carcinoma remains to be further characterized. Rationale for NAC includes downstaging on final pathology and optimization of microscopically negative margins (R0 resection). We investigated rates of neoadjuvant chemotherapy use in advanced sigmoid colon cancer at academic cancer centers and assessed factors associated with likelihood of NAC administration.

METHODS

The National Cancer Database was queried from 2004 to 2017 for patients with clinical T3 or T4, N0-2, M0 sigmoid colon cancer who underwent surgical resection. Those with neoadjuvant radiation or metastatic disease were excluded. The outcomes of patients who did and did not receive neoadjuvant chemotherapy were evaluated for this retrospective cohort study.

RESULTS

There were 23,597 patients of whom 364 (1.5%) received NAC. More patients received NAC at academic (41%, P < .001) and high-volume centers (27%, P < .001). Patients with Medicare/Medicaid (39%) and private insurance (52%) were more likely to receive NAC (P < .001). There was a significantly higher rate of N2 to N1 downstaging in the NAC group. Propensity-score matching demonstrated comprehensive community cancer programs (CCCP) were less likely to provide NAC (OR 0.4; 95% CI 0.23, 0.70, P < .001). There was no difference in survival (P = .20), R0 resection (P = .090), or 30-day readmission rates (P = .30) in the NAC cohort compared to the non-NAC cohort.

CONCLUSIONS

Access to centers offering multi-disciplinary care with NAC prior to surgical resection is important. This care was associated with academic and high-volume centers and private or government-sponsored insurance. There was no difference in survival between NAC and non-NAC cohort.

Successful multidisciplinary treatment for synchronous advanced esophageal and cecal cancers after total gastrectomy with reconstruction by jejunal interposition

BACKGROUND

Esophageal squamous cell carcinoma is characterized by field cancerization, wherein multiple cancers occur in the esophagus, head and neck, and stomach. Synchronous esophageal and colorectal cancers are also encountered with a certain frequency. A good prognosis can be expected if the tumors in both locations can be safely and completely removed. For patients with multiple cancers that occur simultaneously with esophageal cancer, it is necessary to perform a staged operation, taking into consideration the associated surgical invasiveness. It is also necessary to select multidisciplinary treatment depending on the degree of progression of the multiple lesions. We report our rare experience with a staged operation for a patient with synchronous advanced cancers of the esophagus and cecum who had previously undergone total gastrectomy with reconstruction by jejunal interposition for gastric cancer.

CASE PRESENTATION

A 71-year-old man with a history of reconstruction by jejunal interposition after total gastrectomy was diagnosed as having multiple synchronous esophageal and cecal cancers. After neoadjuvant chemotherapy, we performed a planned two-stage operation, with esophagectomy and jejunostomy in the first stage and ileocecal resection and jejunal reconstruction with vascular anastomosis in the second. Postoperatively, the patient was relieved without major complications, and both tumors were amenable to curative pathologic resection.

CONCLUSIONS

Our procedure reported here may be recommended as an option for staged resection and reconstruction in patients with simultaneous advanced esophageal and cecal cancer after total gastrectomy.

Inositol hexaphosphate enhances chemotherapy by reversing senescence induced by persistently activated PERK and diphthamide modification of eEF2

Oxaliplatin is an important initial chemotherapy benefiting advanced-stage colorectal cancer patients. Frustratingly, acquired oxaliplatin resistance always occurs after sequential chemotherapy with diverse antineoplastic drugs. Therefore, an exploration of the mechanism of oxaliplatin resistance formation in-depth is urgently needed. We generated oxaliplatin-resistant colorectal cancer models by four representative compounds, and RNA-seq revealed that oxaliplatin resistance was mainly the result of cells' response to stimulus. Moreover, we proved persistent stimulus-induced endoplasmic reticulum stress (ERs) and associated cellular senescence were the core causes of oxaliplatin resistance. In addition, we screened diverse phytochemicals for ER inhibitors in silico, identifying inositol hexaphosphate (IP6), whose strong binding was confirmed by surface plasmon resonance. Finally, we confirmed the ability of IP6 to reverse colorectal cancer chemoresistance and investigated the mechanism of IP6 in the inhibition of diphthamide modification of eukaryotic elongation factor 2 (eEF2) and PERK activation. Our study demonstrated that oxaliplatin resistance contributed to cell senescence induced by persistently activated PERK and diphthamide modification of eEF2 levels, which were specifically reversed by combination therapy with IP6.

The diagnostic accuracy of local staging in colon cancer based on computed tomography (CT): evaluating the role of extramural venous invasion and tumour deposits

PURPOSE

The shift from adjuvant to neoadjuvant treatment in colon cancer demands the radiological selection of patients for systemic therapy. The aim of this study was to evaluate the accuracy of the CT-based TNM stage and high-risk features, including extramural venous invasion (EMVI) and tumour deposits, in the identification of patients with histopathological advanced disease, currently considered for neoadjuvant treatment (T3-4 disease).

METHODS

All consecutive patients surgically treated for non-metastatic colon cancer between January 2018 and January 2020 in a referral centre for colorectal cancer were identified retrospectively. All tumours were staged on CT according to the TNM classification system. Additionally, the presence of EMVI and tumour deposits on CT was evaluated. The histopathological TNM classification was used as reference standard.

RESULTS

A total of 176 patients were included. Histopathological T3-4 colon cancer was present in 85.0% of the patients with CT-detected T3-4 disease. Histopathological T3-4 colon cancer was present in 96.4% of the patients with CT-detected T3-4 colon cancer in the presence of both CT-detected EMVI and CT-detected tumour deposits. Histopathological T0-2 colon cancer was present in 50.8% of the patients with CT-detected T0-2 disease, and in 32.4% of the patients without CT-detected EMVI and tumour deposits.

CONCLUSION

The diagnostic accuracy of CT-based staging was comparable with previous studies. The presence of high-risk features on CT increased the probability of histopathological T3-4 colon cancer. However, a substantial part of the patients without CT-detected EMVI and tumour deposits was diagnosed with histopathological T3-4 disease. Hence, more accurate selection criteria are required to correctly identify patients with locally advanced disease.

Positive outcomes with neoadjuvant chemotherapy in the management of colovesical fistula in cancer: a case report and literature review

Colovesical fistula (CVF) is usually developed from colonic diverticulitis, followed by tumor. Traditional surgery is usually completed in one or more stages. For complex cancerous CVF, radical resection is more difficult. We report a 62-year-old male patient diagnosed with sigmoid colon cancer combined with sigmoid vesical fistula. In the course of treatment, in addition to conventional surgery, neoadjuvant chemotherapy (NAC) was innovatively used. The sigmoid tumor and fistula were significantly shrunken. Radical surgery achieved negative margins.

Potential therapeutic target for polysaccharide inhibition of colon cancer progression

In recent years, colon cancer has become one of the most common malignant tumors worldwide, posing a great threat to human health. Studies have shown that natural polysaccharides have rich biological activities and medicinal value, such as anti-inflammatory, anti-cancer, anti-oxidation, and immune-enhancing effects, especially with potential anti-colon cancer mechanisms. Natural polysaccharides can not only protect and enhance the homeostasis of the intestinal environment but also exert a direct inhibition effect on cancer cells, making it a promising strategy for treating colon cancer. Preliminary clinical experiments have demonstrated that oral administration of low and high doses of citrus pectin polysaccharides can reduce tumor volume in mice by 38% (p < 0.02) and 70% (p < 0.001), respectively. These results are encouraging. However, there are relatively few clinical studies on the effectiveness of polysaccharide therapy for colon cancer, and ensuring the effective bioavailability of polysaccharides in the body remains a challenge. In this article, we elucidate the impact of the physicochemical factors of polysaccharides on their anticancer effects and then reveal the anti-tumor effects and mechanisms of natural polysaccharides on colon cancer. Finally, we emphasize the challenges of using polysaccharides in the treatment of colon cancer and discuss future applications.

Prognostic impact of extramural venous invasion detected by contrast-enhanced CT colonography in colon cancer

BACKGROUND

The impact of computed tomography (CT)-detected extramural venous invasion on the recurrence of colon cancer is not fully understood. The aim of this study was to investigate the clinical significance of extramural venous invasion diagnosed before surgery by contrast-enhanced CT colonography using three-dimensional multiplanar reconstruction images.

METHODS

Patients with colon cancer staged greater than or equal to T2 and/or stage I-III who underwent contrast-enhanced CT colonography between 2013 and 2018 at the National Cancer Center Hospital in Japan were retrospectively investigated for CT-detected extramural venous invasion. Inter-observer agreement for the detection of CT-detected extramural venous invasion was evaluated and Kaplan-Meier survival curves were plotted for recurrence-free survival using CT-TNM staging and CT-detected extramural venous invasion. Preoperative clinical variables were analysed using Cox regression for recurrence-free survival.

RESULTS

Out of 922 eligible patients, 544 cases were analysed (50 (9.2 per cent) were diagnosed as positive for CT-detected extramural venous invasion and 494 (90.8 per cent) were diagnosed as negative for CT-detected extramural venous invasion). The inter-observer agreement for CT-detected extramural venous invasion had a κ coefficient of 0.830. The group positive for CT-detected extramural venous invasion had a median follow-up of 62.1 months, whereas the group negative for CT-detected extramural venous invasion had a median follow-up of 60.7 months. When CT-TNM stage was stratified according to CT-detected extramural venous invasion status, CT-T3 N(-)extramural venous invasion(+) had a poor prognosis compared with CT-T3 N(-)extramural venous invasion(-) and CT-stage I (5-year recurrence-free survival of 50.6 versus 89.3 and 90.1 per cent respectively; P < 0.001). In CT-stage III, the group positive for CT-detected extramural venous invasion also had a poor prognosis compared with the group negative for CT-detected extramural venous invasion (5-year recurrence-free survival of 52.0 versus 78.5 per cent respectively; P = 0.003). Multivariable analysis revealed that recurrence was associated with CT-T4 (HR 3.10, 95 per cent c.i. 1.85 to 5.20; P < 0.001) and CT-detected extramural venous invasion (HR 3.08, 95 per cent c.i. 1.90 to 5.00; P < 0.001).

CONCLUSION

CT-detected extramural venous invasion was found to be an independent predictor of recurrence and could be used in combination with preoperative TNM staging to identify patients at high risk of recurrence.

Sinapine thiocyanate exhibited anti-colorectal cancer effects by inhibiting KRT6A/S100A2 axis

Sinapine thiocyanate (ST), an alkaloid existed extensively in seeds of cruciferous plants, exhibits a number of pharmacological effects, including anti-inflammatory and anti-malignancy properties. However, it is still unknown what effects and molecular mechanisms ST has on colorectal cancer (CRC). In the current study, it was indicated that ST inhibited proliferation, colony formation, and apoptosis in vitro, as well as arrested the G1 phase of CRC cells. There was a significant repressive effects of ST on invasion and migration of CRC cells in vitro. RNA-sequencing indicated that 750 differentially expressed genes existed in CRC cells after ST treatment, and enrichment analysis demonstrated that ST obviously decreased the activation of keratinization pathways. Among DEGs enriched in keratinization, keratin 6A (KRT6A) was decreased the most significant, as well as its target gene S100 calcium-binding protein A2 (S100A2). Low expression of KRT6A and S100A2 signatures indicated a favorable prognosis in CRC patients. Moreover, we found overexpression of KRT6A relieved the inhibitory effects of ST in CRC cells. Furthermore, ST inhibited the CRC cell proliferation in vivo, and reduced KRT6A and KI67 expression in xenograft tumor. Taken together, we demonstrated that ST exhibited anti-CRC properties by inhibiting KRT6A/S100A2 axis. It is possible that ST can be used as a treatment for CRC.

Is There a Role for Neoadjuvant Systemic Therapy for cT4bM0 Colon Cancer? A Propensity Score-Matched Analysis of the National Cancer Database

BACKGROUND

Nonmetastatic T4b colon cancer has been traditionally treated with upfront surgery, often requiring technically challenging multiorgan resection. Neoadjuvant chemotherapy can potentially downsize these tumors and improve their resectability.

OBJECTIVE

This study aimed to explore trends and outcomes of neoadjuvant chemotherapy use compared to upfront surgery in patients with nonmetastatic T4b colon cancer. This study also sought to determine factors associated with increased neoadjuvant chemotherapy use and with overall survival.

DESIGN

Retrospective cohort study.

SETTINGS

Conducted using the National Cancer Database.

PATIENTS

Patients with nonmetastatic T4b colon cancer who underwent colectomy (2006-2016) were included in the study. Patients receiving neoadjuvant chemotherapy were propensity-matched (1:2) to those who underwent upfront surgery in either clinically node-negative or node-positive disease.

MAIN OUTCOME MEASURES

Postoperative outcomes (length of stay, 30-d readmission, 30/90-d mortality), oncologic resection adequacy (R0 rate, number of resected/positive nodes), and overall survival were the main outcome measures.

RESULTS

Neoadjuvant chemotherapy was used in 7.7% of the patients. Neoadjuvant chemotherapy use increased over the study period from 4% to 16% in the entire cohort, from 3% to 21% in patients with clinically node-positive disease, and from 6% to 12% in patients with clinically node-negative disease. Factors associated with increased use of neoadjuvant chemotherapy included younger age (OR 0.97; 95% CI, 0.96-0.98; p < 0.001), male sex (OR 1.35; 95% CI, 1.11-1.64; p = 0.002), recent diagnosis year (OR 1.16; 95% CI, 1.12-1.20; p < 0.001), academic centers (OR 2.65; 95% CI, 2.19-3.22; p < 0.001), clinically node-positive (OR 1.23; 95% CI, 1.01-1.49; p = 0.037), and tumor located in the sigmoid colon (OR 2.44; 95% CI, 1.97-3.02; p < 0.001). Patients who received neoadjuvant chemotherapy had significantly higher R0 resection compared with upfront surgery (87% vs 77%; p < 0.001). On multivariable analysis, neoadjuvant chemotherapy was associated with higher overall survival (HR 0.76; 95% CI, 0.64-0.91; p = 0.002). On propensity-matched analyses, neoadjuvant chemotherapy was associated with a higher 5-year overall survival compared to upfront surgery in patients with clinically node-positive disease (57% vs 43%; p = 0.003) but not in patients with clinically node-negative disease (61% vs 56%; p = 0.090).

LIMITATIONS

Retrospective design.

CONCLUSION

Neoadjuvant chemotherapy use for nonmetastatic T4b has increased significantly on the national level, more so in patients with clinically node-positive disease. Patients with node-positive disease treated with neoadjuvant chemotherapy had higher overall survival compared to those who underwent upfront surgery. See Video Abstract at http://links.lww.com/DCR/C228 .

EXISTE LUGAR PARA LA TERAPIA SISTMICA NEOADYUVANTE PARA EL CNCER DE COLON CTBM UN ANLISIS EMPAREJADO DE PUNTAJE DE PROPENSIN DE LA BASE DE DATOS NACIONAL DEL CNCER

ANTECEDENTES:El cáncer de colon T4b no metastásico se ha tratado tradicionalmente con cirugía inicial, que frecuentemente requiere de una resección multiorgánica técnicamente desafiante. La quimioterapia neoadyuvante puede potencialmente reducir el tamaño y mejorar la resecabilidad de esos tumores.OBJETIVO:Explorar las tendencias y los resultados del uso de quimioterapia neoadyuvante en pacientes con cáncer de colon T4b no metastásico, en comparación con la cirugía inicial. Determinar los factores asociados con el aumento del uso de quimioterapia neoadyuvante y con la supervivencia general.DISEÑO:Estudio de cohorte retrospectivo.AJUSTES:Utilizando de la Base de Datos Nacional del Cáncer.PACIENTES:Pacientes con cáncer de colon T4b no metastásico sometidos a colectomía (2006-2016). Los pacientes que recibieron quimioterapia neoadyuvante fueron emparejados por propensión (1:2) con aquellos sometidos a cirugía inicial, ya sea en enfermedad clínica con ganglios negativos o ganglios positivos.PRINCIPALES MEDIDAS DE RESULTADO:Resultados posoperatorios (duración de la hospitalización, reingreso a los 30 días, mortalidad a los 30/90 días), adecuación de la resección oncológica (tasa R0, número de ganglios resecados/positivos) y supervivencia general.RESULTADOS:La quimioterapia neoadyuvante se utilizó en el 7,7% de los pacientes. El uso de quimioterapia neoadyuvante aumentó durante el período de estudio del 4% al 16% en toda la cohorte; del 3% al 21% en pacientes con enfermedad clínica y ganglios positivos; y del 6% al 12% en pacientes con enfermedad clínica y ganglios negativos. Los factores asociados con un mayor uso de quimioterapia neoadyuvante incluyeron, edad más joven (OR 0,97, IC del 95 %: 0,96-0,98, p < 0,001), sexo masculino (OR 1,35, IC del 95 %: 1,11-1,64, p = 0,002), año de diagnóstico mas reciente (OR 1,16, 95% IC: 1,12-1,20, p < 0,001), centros académicos (OR 2,65, 95% IC: 2,19-3,22, p < 0,001), enfermedad clínica con ganglios positivos (OR 1,23, 95% IC: 1,01-1,49, p = 0,037), y tumor localizado en colon sigmoide (OR 2,44, 95% IC: 1,97-3,02, p < 0,001). Los pacientes que recibieron quimioterapia neoadyuvante tuvieron una resección R0 significativamente mayor en comparación con la cirugía inicial (87 % frente a 77 %, p < 0,001). En análisis multivariable, la quimioterapia neoadyuvante se asoció con una mayor supervivencia global (HR 0,76, IC del 95%: 0,64-0,91, p = 0,002). En los análisis de propensión pareada, la quimioterapia neoadyuvante se asoció con una mayor supervivencia general a los 5 años en comparación con la cirugía inicial en pacientes con enfermedad clínica con ganglios positivos (57% frente a 43%, p = 0,003), pero no en pacientes con enfermedad clínica y ganglios negativos (61% vs 56%, p = 0,090).LIMITACIONES:Diseño retrospectivo.CONCLUSIÓN:El uso de quimioterapia neoadyuvante para T4b no metastásico ha aumentado significativamente a nivel nacional, más aún en pacientes con enfermedad clínica y ganglios positivos. Los pacientes con enfermedad y ganglios positivos tratados con quimioterapia neoadyuvante tuvieron una mayor supervivencia general en comparación con la cirugía inicial. Consulte Video Resumen en http://links.lww.com/DCR/C228 . (Traducción-Dr. Fidel Ruiz Healy ).

Diagnostic Accuracy of Abdominal CT for Locally Advanced Colon Tumors: Can We Really Entrust Certain Decisions to the Reliability of CT?

Many different options of neoadjuvant treatments for advanced colon cancer are emerging. An accurate preoperative staging is crucial to select the most appropriate treatment option. A retrospective study was carried out on a national series of operated patients with T4 tumors. Considering the anatomo-pathological analysis of the surgical specimen as the gold standard, a diagnostic accuracy study was carried out on the variables T and N staging and the presence of peritoneal metastases (M1c). The parameters calculated were sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios, as well as the overall accuracy. A total of 50 centers participated in the study in which 1950 patients were analyzed. The sensitivity of CT for correct staging of T4 colon tumors was 57%. Regarding N staging, the overall accuracy was 63%, with a sensitivity of 64% and a specificity of 62%; however, the positive and negative likelihood ratios were 1.7 and 0.58, respectively. For the diagnosis of peritoneal metastases, the accuracy was 94.8%, with a sensitivity of 40% and specificity of 98%; in the case of peritoneal metastases, the positive and negative likelihood ratios were 24.4 and 0.61, respectively. The diagnostic accuracy of CT in the setting of advanced colon cancer still has some shortcomings for accurate diagnosis of stage T4, correct classification of lymph nodes, and preoperative detection of peritoneal metastases.

Pomolic acid and its glucopyranose ester promote apoptosis through autophagy in HT-29 colon cancer cells

BACKGROUND

Colon cancer remains a leading cause of death globally. Pomolic acid (PA) can be separated from the ethyl acetate fraction of achyrocline satureioides.

AIM

To determine the effects of PA and its glucopyranose ester, pomolic acid-28-O-β-D-glucopyranosyl ester (PAO), on colon cancer HT-29 cells.

METHODS

3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay was used to measure cell viability. Apoptosis was detected via hoechst 33342 staining. PI single staining was identified by flow cytometry to determine the cycle and scratch assay was used to observe the migration of HT-29 cells. The levels of mRNA and proteins were evaluated by q polymerase chain reaction and western blotting, respectively.

RESULTS

PA and PAO considerably inhibited the growth of the HT-29 cell line in a time and dose-dependent manner. After the administration of PA and PAO for 24 and 48 h, cell apoptosis was significantly promoted and HT-29 cells were arrested in the G0/G1 stage. The Bax/Bcl2 ratio was also increased, which activated cysteinyl aspartate specific proteinase 3, leading to apoptosis; it also increased the expression of light chain 3 II/I and Beclin1, which activated autophagy and caused cell death. This in turn increased the expression of p62 to promote cell apoptosis, inhibiting the levels of signal transducer and activator of transcription 3 (STAT3) and p-STAT3, suppressing the level of Bcl2, and promoting cell.

CONCLUSION

Both PA and PAO provide novel therapeutic strategies for treating colorectal cancer.

Adjuvant and Neoadjuvant Treatments for Resectable Hepatocellular Carcinoma

PURPOSE OF REVIEW

This review provides an update on the developments of adjuvant and neoadjuvant liver-directed and systemic therapy options for patients with resectable hepatocellular carcinoma.

RECENT FINDINGS

Data on liver-directed treatment in the adjuvant and neoadjuvant settings are sparse and results are conflicting; many studies suggest that optimizing patient selection criteria is a key milestone required to improve study design and clinical benefit to patients. Systemic treatment options are primarily focused on investigation of anti-PD-1/L1 immunotherapeutic agents, either alone or in combination with other drugs. Numerous clinical trials in both adjuvant and neoadjuvant settings are in progress. Exploration of liver-directed and systemic treatment options for adjuvant and neoadjuvant treatment of patients with resectable hepatocellular carcinoma has the potential to improve clinical outcomes for this patient population.

Impact of neoadjuvant chemotherapy for locally advanced colon cancer on postoperative complications

PURPOSE

Although not considered standard therapy, neoadjuvant chemotherapy (NAC) is an encouraging alternative for selected patients with locally advanced colon cancer (LAC). The aim of this study was to compare 30-day postoperative outcomes between patients undergoing upfront surgery and those undergoing NAC for LAC.

METHODS

Using the ACS-NSQIP data from 2016 to 2020, 11,498 patients with LAC were divided into those who underwent upfront colectomy (96.2%) and those who received NAC (3.8%). The primary outcome was a composite outcome encompassing 30-day major postoperative complications. Propensity score matched (PSM) analysis and multivariable logistic regression were performed.

RESULTS

After PSM analysis, there was no statistically significant difference in the development of a major complication. NAC was not significantly associated with the primary outcome. Risk factors for postoperative complications were T4 stage, older age, male sex, black race, smoking, dependent status, severe COPD, hypoalbuminemia, and preoperative transfusion. Laparoscopic and robotic surgery was protective.

CONCLUSION

NAC did not increase the odds of developing a major complication.

Early-Onset Colon Cancer: A Narrative Review of Its Pathogenesis, Clinical Presentation, Treatment, and Prognosis

Colon cancer remains a leading cause of cancer-related deaths, and there has been a rise in the incidence of early-onset colon cancer or colon cancer diagnosed before the age of 50 years old. Early-onset colon cancer has several differences in clinical presentation, as well as histopathology, genetic alteration, and molecular profiling. Early-onset colon cancer can be differentiated into familial type that includes hereditary familial syndrome and sporadic type. Demographic variance also exists in both developing and developed countries. Due to the rising incidence of colon cancer diagnosed in younger age, it is imperative to examine the available evidence regarding the mortality rate of early-onset colon cancer. Colon cancer is affected by numerous modifiable and non-modifiable risk factors. Increasing obesity and lifestyle disorders in the younger population, such as smoking, may influence this increasing trend. There are existing guidelines for colon cancer screening in both average-risk and high-risk individuals. This narrative review aims to highlight the pathogenesis of early-onset CRC; its clinical presentation, treatment, prognosis; and how it differs from late-onset CRC.

Evaluating the oncological safety of neoadjuvant chemotherapy in locally advanced colon carcinoma: a systematic review and meta-analysis of randomised clinical trials and propensity-matched studies

PURPOSE

Use of neoadjuvant chemotherapy (NAC) for locally advanced colon cancer (LACC) remains controversial. An integrated analysis of data from high-quality studies may inform the long-term safety of NAC for this cohort. Our aim was to perform a systematic review and meta-analysis of randomised clinical trials (RCTs) and propensity-matched studies to assess the oncological safety of NAC in patients with LACC.

METHODS

A systematic review was performed as per preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Survival was expressed as hazard ratios using time-to-effect generic inverse variance methodology, while surgical outcomes were expressed as odds ratios (ORs) using the Mantel-Haenszel method. Data analysis was performed using Review Manager version 5.4.

RESULTS

Eight studies (4 RCTs and 4 retrospective studies) including 31,047 patients with LACC were included. Mean age was 61.0 years (range: 19-93 years) and mean follow-up was 47.6 months (range: 2-133 months). Of those receiving NAC, 4.6% achieved a pathological complete response and 90.6% achieved R0 resection (versus 85.9%, P < 0.001). At 3 years, patients receiving NAC had improved disease-free survival (DFS) (OR: 1.28, 95% confidence interval (CI): 1.02-1.60, P = 0.030) and overall survival (OS) (OR: 1.76, 95% CI: 1.10-2.81, P = 0.020). When using time-to-effect modelling, a non-significant difference was observed for DFS (HR: 0.79, 95% CI: 0.57-1.09, P = 0.150) while a significant difference in favour of NAC was observed for OS (HR: 0.75, 95% CI: 0.58-0.98, P = 0.030).

CONCLUSION

This study highlights the oncological safety of NAC for patients being treated with curative intent for LACC using RCT and propensity-matched studies only. These results refute current management guidelines which do not advocate for NAC to improve surgical and oncological outcomes in patients with LACC.

TRIAL REGISTRATION

International Prospective Register of Systematic Review (PROSPERO) registration: CRD4202341723.

MBD3 as a Potential Biomarker for Colon Cancer: Implications for Epithelial-Mesenchymal Transition (EMT) Pathways

The tumor EMT is a crucial event in tumor pathogenesis and progression. Previous research has established MBD3's significant role in pancreatic cancer EMT. However, MBD3's precise role in colon cancer remains unclear and warrants further investigation. Pan-cancer analysis revealed MBD3's differential expression in various tumors and its significant association with tumor occurrence, growth, and progression. Moreover, analysis of single-cell sequencing and clinical data for colon cancer revealed MBD3 expression's negative correlation with clinical indicators such as survival prognosis. Functional enrichment analysis confirmed the association between MBD3 and EMT in colon cancer. Pathological examinations, western blotting, and qRT-PCR in vitro and in vivo validated MBD3's differential expression in colon cancer. Transwell, CCK-8, clone formation, and in vivo tumorigenesis experiments confirmed MBD3's impact on migration, invasion, and proliferation. Our findings demonstrate MBD3 as a potential prognostic marker and therapeutic target for colon cancer.

Open, Laparoscopic, and Robotic Approaches to Treat Colorectal Cancer: A Comprehensive Review of Literature

Surgery is usually required to treat colorectal cancer (CRC). Medical technology has advanced, providing various approaches to tackle this disease. Different surgeries are available, such as laparoscopic surgery, single-incision laparoscopic surgery, natural orifice transluminal endoscopic surgery, and robotic surgery. Laparoscopic surgery has several benefits including reduced blood loss and shorter recovery time. It can also improve lung function and minimize complications. However, it requires more time to perform and has a higher risk of complications during the procedure. Robotic surgery provides a three-dimensional view of the surgical area allowing for greater precision in rectal surgeries and access to difficult-to-reach pelvic regions. This method utilizes robotics technology which reduces surgical time and speeds up recovery for patients. There are various surgical options available for treating CRC; however, laparoscopic surgery and robotic surgery offer unique advantages despite their own drawbacks. As technology continues to evolve, medical techniques will continue improving existing methods while providing new options resulting in better outcomes for patients. Compared to laparoscopy, robotic surgery has a lower rate of operative conversions and a shorter learning curve. However, it also has some drawbacks, such as a longer docking time, lack of tactile sensation, and higher cost. Therefore, the choice of surgical method should depend on patient characteristics, surgeon preference and expertise, and available resources. Currently, specialized centers offer robotic surgeries which are more expensive and take longer compared to open and laparoscopic approaches. Nonetheless, they are considered safe and feasible when compared to traditional surgery. Short-term outcomes for robotic surgeries are better, while long-term postoperative complication rates remain similar. However, there is a need for additional well-defined randomized control trials conducted across multiple centers to validate the use of robotic surgery over open and laparoscopic approaches. Improving patient care and outcomes is the objective of this comprehensive literature overview on surgical approaches for CRC.

Exosomes as a Source of Biomarkers for Gastrointestinal Cancers

Exosomes are small, lipid-bilayer bound extracellular vesicles of 40-160 nanometers in size that carry important information for intercellular communication. Exosomes are produced more by tumor cells than normal cells and carry tumor-specific content, such as DNA, RNA, and proteins, which have been implicated in tumorigenesis, tumor progression, and treatment response. Due to the critical role of exosomes in cancer development and progression, they can be exploited to develop specific biomarkers and therapeutic targets. Since exosomes are present in various biofluids, such as blood, saliva, urine, and peritoneal fluid, they are ideally suited to be developed as liquid biopsy tools for early diagnosis, molecular profiling, disease surveillance, and treatment response monitoring. In the past decade, numerous studies have been published about the functional significance of exosomes in a wide variety of cancers, with a particular focus on exosome-derived RNAs and proteins as biomarkers. In this review, utilizing human studies on exosomes, we highlight their potential as diagnostic, prognostic, and predictive biomarkers in gastrointestinal cancers.

Pathological response and safety of FOLFOXIRI for neoadjuvant treatment of high-risk relapsed locally advanced colon cancer: study protocol for a single-arm, open-label phase II trial

INTRODUCTION

Neoadjuvant chemotherapy (NAC) has been demonstrated effective in several tumours, but its benefit has not yet been elucidated in colorectal cancer, especially locally advanced colorectal cancer (LACRC).

METHODS AND ANALYSIS

This is a single-arm, open-label, prospective phase II exploratory clinical trial. Patients with LACRC will receive four cycles of NAC with 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI), followed by operation and then adjuvant chemotherapy with capecitabine and oxaliplatin for two to five cycles or single-agent capecitabine for five cycles, or observation. The primary endpoint is the rate of tumour regression grade (TRG) 0-2 in the resected tumour tissue, which is evaluated by experienced pathologists according to the Ryan R TRG grading system. Secondary endpoints include objective response rate, pathologic complete response, microscopically complete resection rate, progression-free survival, distant metastasis-free survival, overall survival, toxicity and compliance to study treatment, molecular markers, quality of life to study treatment and the number of patients with 30-day postoperative mortality. The objective of this study is to analyse the efficacy and safety of FOLFOXIRI as the NAC regimen in patients with LACRC and to identify a promising treatment strategy in this setting.

ETHICS AND DISSEMINATION

Written informed consent will be required from and provided by all patients enrolled. The study protocol has been approved by the independent ethics committee of West China Hospital, Sichuan University (approval number: 2021403). This study will demonstrate the potential benefit of NAC with the FOLFOXIRI regimen. Results will be shared with policymakers and the academic community to promote the clinical management of colon cancer.

TRIAL REGISTRATION NUMBER

NCT05018182.

Meta-analysis of neoadjuvant immunotherapy for non-metastatic colorectal cancer

Background

Immunotherapy has been approved for the treatment of metastatic colorectal cancer. The efficacy and safety of neoadjuvant immunotherapy for the treatment of non-metastatic colorectal cancer remains unclear. We tried to explore clinical effect of neoadjuvant immunotherapy in the treatment of non-metastatic colorectal cancer.

Methods

We searched the databases (PubMed, Wanfang Embase, Cochrane Library and China National Knowledge Infrastructure databases) to obtain suitable articles up to September 2022. The primary outcomes of pathological complete response (pCRs), major pathological response (MPR), objective response rate (ORR), R0-resection and anus preserving rate were collected and evaluated. Secordary outcomes (pCRs and MPR) of subgroup analysis between deficient mismatch repair/microsatellite instability-high group (dMMR/MSI-H) and proficient mismatch repair/microsatellite stable group (pMMR/MSS) and outcomes for rectal cancer were analyzed for the final results.

Results

We included ten articles and 410 cases of non-metastatic colorectal cancer with neoadjuvant immunotherapy. There were 113 (27.5%) cases with the dMMR/MSI-H status and 167 (40.7%) cases with the pMMR/MSS status. pCRs was found in 167/373 (44.6%) patients (ES: 0.49, 95% CI: 0.36 to 0.62, P<0.01, chi² = 65.3, P<0.01, I ² = 86.2%) and MPR was found in 194/304 (63.8%) patients (ES: 0.66, 95% CI: 0.54 to 0.78, P<0.01, chi² = 42.55, P<0.01, I ² = 81.2%) with the random-effects model and huge heterogeneity. In the subgroup analysis, pCRs was higher in the dMMR/MSI-H group than the pMMR/MSS group in the fixed-effects model with minimal heterogeneity (OR: 3.55, 95% CI: 1.74 to 7.27, P<0.01, chi² = 1.86, P=0.6, I ² = 0%). pCRs was found in 58/172 (33.9%) rectal cancer patients (ES: 0.33, 95% CI: 0.26 to 0.40, P<0.01, chi² = 3.04, P=0.55, I ² = 0%) with the fixed-effects model and little heterogeneity.

Conclusion

Neoadjuvant immunotherapy could increase pCRs and MPR rate for non-metastatic colorectal cancer. Neoadjuvant immunotherapy could achieve better pCRs rate in dMMR/MSI-H group than in the pMMR/MSS group. Neoadjuvant immunotherapy could be another treatment option for non-metastatic colorectal cancer.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#myprospero, identifier CRD42022350523.

A novel potential inflammation-nutrition biomarker for predicting lymph node metastasis in clinically node-negative colon cancer

Background

The purpose of this study is to investigate the predictive significance of (platelet × albumin)/lymphocyte ratio (PALR) for lymph node metastasis (LNM) in patients with clinically node-negative colon cancer (cN0 CC).

Methods

Data from 800 patients with primary CC who underwent radical surgery between March 2016 and June 2021 were reviewed. The non-linear relationship between PALR and the risk of LNM was explored using a restricted cubic spline (RCS) function while a receiver operating characteristic (ROC) curve was developed to determine the predictive value of PALR. Patients were categorized into high- and low-PALR cohorts according to the optimum cut-off values derived from Youden's index. Univariate and multivariate logistic regression analyses were used to identify the independent indicators of LNM. Sensitivity analysis was performed to repeat the main analyses with the quartile of PALR.

Results

A total of eligible 269 patients with primary cN0 CC were retrospectively selected. The value of the area under the ROC curve for PALR for predicting LNM was 0.607. RCS visualized the uptrend linear relationship between PALR and the risk of LNM (p-value for non-linearity > 0.05). PALR (odds ratio = 2.118, 95% confidence interval, 1.182-3.786, p = 0.011) was identified as an independent predictor of LNM in patients with cN0 CC. A nomogram incorporating PALR and other independent predictors was constructed with an internally validated concordance index of 0.637. The results of calibration plots and decision curve analysis supported a good performance ability and the sensitivity analysis further confirmed the robustness of our findings.

Conclusion

PALR has promising clinical applications for predicting LNM in patients with cN0 CC.

Oncologic safety of colonic stenting as a bridge to surgery in left-sided malignant colonic obstruction: Current evidence and prospects

Approximately 7%-29% of patients with colorectal cancer present with colonic obstruction. The concept of self-expandable metal stent (SEMS) insertion as a bridge to surgery (BTS) is appealing. However, concerns on colonic stenting possibly impairing oncologic outcomes have been raised. This study aimed to review current evidence on the short- and long-term oncologic outcomes of SEMS insertion as BTS for left-sided malignant colonic obstruction. For short-term outcomes, colonic stenting facilitates a laparoscopic approach, increases the likelihood of primary anastomosis without a stoma, and may decrease postoperative morbidity. However, SEMS-related perforation also increases local recurrence and impairs overall survival. Moreover, colonic stenting may cause negative oncologic outcomes even without perforation. SEMS can induce shear forces on the tumor, leading to increased circulating cancer cells and aggressive pathological characteristics, including perineural and lymphovascular invasion. The conflicting evidence has led to discordant guidelines. Well-designed collaborative studies that integrate both oncologic outcomes and data on basic research (e.g., alteration of circulating tumors) are needed to clarify the actual benefit of colonic stenting as BTS.

Post-operative anastomotic leakage and collagen changes in patients with rectal cancer undergoing neoadjuvant chemotherapy vs chemoradiotherapy

Background

A significant difference in the anastomotic leakage (AL) rate has been observed between patients with locally advanced rectal cancer who have undergone preoperative chemotherapy and those undergoing preoperative chemoradiotherapy. This study aimed to quantitatively analyse collagen structural changes caused by preoperative chemoradiotherapy and illuminate the relationship between collagen changes and AL.

Methods

Anastomotic distal and proximal "doughnut" specimens from the Sixth Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) were quantitatively assessed for collagen structural changes between patients with and without preoperative radiotherapy using multiphoton imaging. Then, patients treated with preoperative chemoradiotherapy were used as a training cohort to construct an AL-SVM classifier by the Mann-Whitney U test and support vector machine (SVM). An independent test cohort from the Fujian Province Cancer Hospital (Fuzhou, China) was used to validate the AL-SVM classifier.

Results

A total of 207 patients were included from the Sixth Affiliated Hospital of Sun Yat-sen University. The AL rate in the preoperative chemoradiotherapy group (n = 107) was significantly higher than that in the preoperative chemotherapy group (n = 100) (21.5% vs 7.0%, P = 0.003). A fully quantitative analysis showed notable morphological and spatial distribution feature changes in collagen in the preoperative chemoradiotherapy group. Then, the patients who received preoperative chemoradiotherapy were used as a training cohort to construct the AL-SVM classifier based on five collagen features and the tumor distance from the anus. The AL-SVM classifier showed satisfactory discrimination and calibration with areas under the curve of 0.907 and 0.856 in the training and test cohorts, respectively.

Conclusions

The collagen structure may be notably altered by preoperative radiotherapy. The AL-SVM classifier was useful for the individualized prediction of AL in rectal cancer patients undergoing preoperative chemoradiotherapy.

Downregulation of MACC1 facilitates the reversal effect of verapamil on the chemoresistance to active metabolite of irinotecan in human colon cancer cells

The aim of this study is to investigate the reversal effect of verapamil (VER) on chemoresistance to irinotecan (CPT-11) in human colon cancer cells and relevant mechanisms. Cell counting kit-8 (CCK-8) test and colony-forming unit (CFU) experiment results show that VER strengthens the sensitivity of human colon cancer cell line HT29 to CPT-11 but has a small effect on SW480 cells. High-throughput transcriptome sequencing, RT-PCR, and Western blot results show that the inhibition of metastasis-associated in colon cancer-1 (MACC1) expression by VER is the key factor for reversal effect on chemoresistance to CPT-11. Transfection experiments further show that VER can reverse the resistance of human colon cancer cells to SN-38, the active metabolite of CPT-11, when MACC1 is overexpressed. The nude mouse transplantation tumor experiment provides an in vivo proof that VER can strengthen sensitivity to CPT-11 in drug-resistant human colon cancer cells, and the effect might be related to the inhibited expression of MACC1. In summary, VER might strengthen the reversal effect of VER on chemoresistance to CPT-11 in human colon cancer cells and facilitate the apoptosis of human colon cancer cells by downregulating MACC1 expression.

Prognostic value of final pathological stage in colon adenocarcinoma after neoadjuvant chemotherapy: A propensity score-matched study

Background

Neoadjuvant chemotherapy (NAC) could improve local tumor control of locally advanced colon cancer (LACC), but the prognostic value of yp stage in colon cancer remains unknown. Here, we aimed to ascertain yp stage as an indicator for LACC prognosis after NAC.

Methods

The data of patients diagnosed with colon adenocarcinoma between 2004 and 2015 were extracted from the Surveillance, Epidemiology, and End Results database. After 1:2 propensity score matching, cancer-specific survival (CSS) and overall survival (OS) were compared between the NAC and Non-NAC groups of different stage classifications. The correlation between clinical and pathological factors and CSS was identified.

Results

A total of 49, 149, and 81 matched pairs of stage 0-I, II, and III patients, respectively, were generated for analysis. For stage 0-I (p = 0.011) and III (p = 0.015), only CSS in the NAC groups were inferior. Receiving NAC was an independent prognostic risk factor for patients with stage 0-I (hazard ratio, 7.70; 95% confidence interval, 1.820-32.5; p = 0.006) and stage III (hazard ratio, 1.73; 95% confidence interval, 1.11-2.68; p = 0.015).

Conclusions

The CSS was poorer among LACC patients who underwent NAC than among those who did not. The yp stage of colon cancer after NAC has distinctive significance, which may contribute to predicting the prognosis and guiding the treatment of LACC patients after NAC.

The role of neoadjuvant chemotherapy in patients with locally advanced colon cancer: A systematic review and meta-analysis

BACKGROUND

Controversy persists about neoadjuvant chemotherapy (NAC) within the field of locally advanced colon cancer (LACC). The purpose of this study was to assess the existing and latest literature with high quality to determine the role of NAC in various aspects.

METHODS

A comprehensive literature search of the PubMed, Embase, Web of Science, and the Cochrane Library databases was conducted from inception to April 2022. Review Manager 5.3 was applied for meta-analyses with a random-effects model whenever possible.

RESULTS

Overall, 8 studies were included in this systematic review and meta-analysis, comprising 4 randomized controlled trials (RCTs) and 4 retrospective studies involving 40,136 participants. The 3-year overall survival (OS) (HR: 0.90, 95% CI: 0.66-1.23, P = 0.51) and 5-year OS (HR: 0.89, 95% CI: 0.53-1.03, P = 0.53) were comparable between two groups. Mortality in 30 days was found less frequent in the NAC group (OR: 0.43, 95% CI: 0.20-0.91, P = 0.03), whereas no significant differences were detected concerning other perioperative complications, R0 resection, or adverse events. In terms of subgroup analyses for RCTs, less anastomotic leak (OR: 0.51, 95% CI: 0.31-0.86, P = 0.01) and higher R0 resection rate (OR: 2.35, 95% CI: 1.04-5.32, P = 0.04) were observed in the NAC group.

CONCLUSIONS

NAC is safe and feasible for patients with LACC, but no significant survival benefit could be demonstrated. The application of NAC still needs to be prudent until significant evidence supporting the oncological outcomes is presented.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero, identifier (CRD42022333306).

Prehabilitation. An Interdisciplinary Patient-Centric Conceptual Framework

OBJECTIVES

To review the recent literature around patient-centric prehabilitation in oncology patients and propose a conceptual framework to inform development of interdisciplinary prehabilitation services leading to focused, individualized prehabilitation interventions.

DATA SOURCES

A review of recent peer-reviewed literature, national guidance, and government strategy on prehabilitation in oncology patients.

CONCLUSION

Patient- centric prehabilitation is key to improving patient's experiences of cancer throughout the cancer journey while improving population health and reducing financial costs. Successful personalized prehabilitation interventions are comprised of an interplay between individual interdisciplinary roles, as illustrated in the conceptual framework. The role of the nurse underpins this whole process in patient screening, assessment, implementation of the intervention, and patient reassessment, ensuring care is dynamic and tailored to patient need.

IMPLICATIONS FOR NURSING PRACTICE

The review has discussed the key role that nurses play in the process but warrants more research in the area. The conceptual framework provides a basis to develop interdisciplinary prehabilitation services underpinned by the nurse's role. The review advocates the use of educational interventions to equip all health professionals with prehabilitation knowledge to enable interdisciplinary prehabilitation services to be developed.

The efficiency of neoadjuvant chemotherapy in colon cancer with mismatch repair deficiency

Colon cancers with mismatch repair deficiency (dMMR) have specific clinicopathologic characteristics compared with mismatch repair proficiency (pMMR); however, the effect of MMR status on the efficiency of neoadjuvant chemotherapy (NCT) remains unclear. In our study, 439 dMMR and 26 pMMR colon cancer patients with or without NCT from 2010 to 2017 were retrospectively collected. Clinicopathological features, treatment response, and survival were compared between different groups. In the dMMR group, patients with NCT were likely to have higher CEA (abnormal CEA: 51.6% vs. 17.4%, p < 0.001), more multiorgan resection (38.7% vs. 16.8%, p = 0.006), and larger postoperative tumor diameter (7.26 vs. 6.21, p = 0.033) than those without NCT, but nearly half of cT4b patients who had NCT (42.9%, 9/21) avoid multiorgan resection. pT4 stage (HR, 14.97; 95% CI, 1.88-118.92; p = 0.010), number of positive lymph nodes (HR, 1.17; 95% CI, 1.09-1.26; p < 0.001), and tumor deposit (HR, 6.73; 95% CI, 2.08-21.74; p = 0.001) were independent prognosis factors of disease-free survival (DFS). For the advanced tumor subset, there is no significant difference between patients with or without NCT for OS (p = 0.13) and DFS (p = 0.11), although the survival rate of NCT was higher than non-NCT patients. Moreover, tumor regression grade was similar between dMMR and pMMR patients who had NCT. This study showed that NCT was more likely to be employed in dMMR patients with advanced tumors and may reduce the rate of multiorgan resection for cT4b dMMR patients. More large-scaled researches are needed to further explore if MMR status could predict the efficacy of neoadjuvant chemotherapy in patients with colon cancer.